Home | About CytoJournalEditorial Board | Archived articles | Search CytoJ Articles | Subscribe | Peer review policies | CytoJournal Quiz Cases
  Reviewer corner | Author corner | OA Steward’s corner | CF member’s corner | Join as CF member | Manuscript submission | Open Access (OA) Advocacy
CytoJournal All 'FULL TEXT' in HTML are FREE under "open access" charter of CytoJournal.
To login for downloading any PDF OR to request TOC (Table of Content) by e-mail, please click here
Home Email this page Print this page Small font size Default font size Increase font size Cytopathology Foundation
Navigate here
Resource links
 »  Similar in PUBMED
 »  Search Pubmed for
 »  Search in Google Scholar for
 »  Article in PDF (2,527 KB)
 »  Citation Manager
 »  Access Statistics
 »  Reader Comments
 »  Email Alert *
 »  Add to My List *
* Registration required (free)  

  In this article
 » Question
 » Answer
 »  Additional Quiz ...
 »  Answers to Addit...
 »  Brief Review of ...
 »  Competing Intere...
 »  Authorship State...
 »  Ethics Statement...
 »  List of Abbrevia...
 »  References
 »  Article Figures

 Article Access Statistics
    PDF Downloaded144    
    Comments [Add]    

Recommend this journal


Browse articles
CytoJournal 2017,  14:11

An elderly man with a solitary liver lesion

1 Department of Pathology and Laboratory Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
2 Department of Dermatology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA

Date of Submission28-Jul-2016
Date of Acceptance03-Oct-2016
Date of Web Publication26-May-2017

Correspondence Address:
Rachel Conrad
Department of Pathology and Laboratory Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/1742-6413.207138

Rights and Permissions

How to cite this article:
Barton L, Zhao L, Doty JN, Stasko T, Conrad R. An elderly man with a solitary liver lesion. CytoJournal 2017;14:11

How to cite this URL:
Barton L, Zhao L, Doty JN, Stasko T, Conrad R. An elderly man with a solitary liver lesion. CytoJournal [serial online] 2017 [cited 2019 Dec 14];14:11. Available from: http://www.cytojournal.com/text.asp?2017/14/1/11/207138

A 77-year-old Caucasian man was being worked up for pneumonia. He was on home oxygen and steroids for severe chronic obstructive pulmonary disease.(COPD) and had a prior biopsy of a lump on the lip at an outside facility many years ago. Computed tomography scan showed an incidental 2.3.cm liver lesion. After resolution of his acute issues, he underwent fine needle aspiration.(FNA) and biopsy of the liver lesion.[Figure 1].
Figure 1: Morphologic findings of the liver lesion fine needle aspiration. (a) A cellular smear with loosely cohesive cells with scant cytoplasm (Romanowsky, ×20); (b) More nuclear detail and the characteristic dusty chromatin (Papanicolaou, ×20); (c) Solid nests of small round blue cells with nuclear crowding (H and E of the cell block, ×20); (d) The characteristic perinuclear dot-like pattern (Cytokeratin-20 of the cell block, ×40)

Click here to view

 » Question Top

What is your interpretation?

  1. Cholangiocarcinoma
  2. Lymphoma
  3. Merkel cell carcinoma
  4. Small cell carcinoma.

 » Answer Top

C. Merkel cell carcinoma (MCC).

MCC is a rare, aggressive, cutaneous neuroendocrine tumor that tends to arise in sun-exposed areas of elderly patients or the setting of immunosuppression. MCC has a poor prognosis, especially when associated with lymph node involvement or metastatic disease. Since it is rare, MCC can be a challenging diagnosis when it involves a noncutaneous site. Aspiration of MCC typically yields relatively monomorphic nuclei with finely granular, dusty chromatin. Nucleoli are not easily observed. Mitotic figures and apoptotic bodies may be prominent, but necrosis is infrequent. Crush artifact and nuclear molding are not typically identified. MCC is notable among neuroendocrine tumors for its characteristic cytokeratin-20 (CK-20) positivity. This stain produces a perinuclear dot-like pattern that highlights spherical cytoplasmic inclusions composed of intermediate keratin filaments.

Small cell carcinoma is one of the most important differential diagnoses for MCC and is usually accompanied by a primary tumor in the lung or gastrointestinal tract. Small cell carcinoma is characterized by syncytial aggregates of cells with high nuclear to cytoplasmic ratios, prominent crush artifact, and nuclear molding. Typically, small cell carcinoma lacks CK-20 staining although it expresses neuroendocrine markers such as MCC.

Other small cell lesions may enter the differential diagnosis of a solitary metastatic lesion sampled by FNA. Lymphomas should display a discohesive pattern with lymphoglandular bodies in the background. Unlike MCC, most lymphomas stain CD45 positive and CD56 negative; this pattern can also be seen on flow cytometry.[1] Cholangiocarcinoma was considered in our liver lesion case, but it typically displays columnar or cuboidal cells in glandular arrangements, with positivity for CK-7 and mucin stains.

Rare entities such as an undifferentiated round cell sarcoma or small cell variants of other tumors may also be considered. Basal cell carcinoma (BCC) is an important differential skin lesion but is unlikely to spread to deep organs. Melanoma can metastasize widely and often is associated with skin lesions; its morphologic appearance can vary, but the loosely cohesive cells classically display a prominent nucleolus, occasional cytoplasmic pigment, and positivity for S100 and other melanoma markers. Metastatic disease should always be considered, and a good clinical history is an important first step in narrowing the differential diagnostic list.

 » Additional Quiz Questions Top

Q1: Which of the following is believed to be the underlying etiology in 70%–80% of MCC cases?

  1. Carcinogens
  2. Hereditary genetic mutations
  3. Oncovirus infection
  4. Trauma.

Q2: According to the American Joint Committee on Cancer (AJCC) staging system for MCC, a solitary distant metastasis to the liver would be classified as which of the following:

  1. Stage I
  2. Stage II
  3. Stage III
  4. Stage IV.

Q3: Which of the following immunohistochemical stain is negative in MCC?

  1. CD56
  2. Chromogranin
  3. CM2B4
  4. CK-7.

 » Answers to Additional Quiz Questions Top

Q1: C; Q2: D; Q3: D.

Q1: C: Research has found that 70%–80% of MCC cases are infected by a small, nonenveloped, double-stranded DNA virus, which was appropriately named Merkel cell polyomavirus (MCPyV or MCV).[2],[3] In tumors with MCPyV, the expression of viral large T antigen with an intact retinoblastoma protein (RB)-binding site is necessary for growth.[4] Recently, whole exome sequencing of MCC has detected a high number of mutations in the retinoblastoma pathway genes in all MCC cases and specifically an RB1 nonsense truncating protein mutation in polyomavirus-negative MCCs.[5]

Q2: D: Previously, five competing staging systems had been used to describe MCC in most publications. Recently, the AJCC defined a new MCC-specific consensus staging system based on tumor, node, and metastases. Stages I and II are diseases localized to the skin, with Stage I being for primary lesions ≤2 cm and Stage II being for primary lesions >2 cm. Stage III is defined as disease involving the regional lymph nodes and Stage IV as distant metastasis.[6] The 5-year disease-specific survival rate is 64%, with disease stage being the only independent predictor of survival (5-year survival for Stage I is 81%; Stage II, 67%; Stage III, 52%; and Stage IV, 11%).[7] High mitotic rate, tumor-infiltrating lymphocytes, positive surgical excision margins, tumor depth <5 mm, and age >75 years have also shown some correlation with a worse prognosis.[8],[9],[10],[11]

Q3: D: MCC typically expresses neuroendocrine markers such as chromogranin, CD56, and synaptophysin. Unlike most neuroendocrine lesions, though, MCC shows perinuclear positivity with CK-20. MCC is negative for CK-7. CM2B4, a relatively new marker that targets MCPyV T-antigen, is expressed in most cases.[12],[13]

 » Brief Review of the Topic Top

Merkel cells are part of a neurite complex important for light-touch responses in the somatosensory system, located in the stratum basale of the epidermis.[14],[15] Human Merkel cells were first described by Merkel in 1875 and named Tastzellen, translating to “touch cells.”[16] MCC was first described as “trabecular carcinoma of the skin” in 1972, and electron microscopy subsequently demonstrated cytoplasmic granules, suggesting an origin from Merkel cells.[17] The term MCC was first used in 1980[18] and is now the most common term for this entity.[19] 70%–80% of MCC cases are related to the MCPyV, and the remaining polyomavirus-negative tumors are associated with mutations in the retinoblastoma gene.[2],[3]

In the United States, approximately 1500 new cases of MCC are diagnosed each year,[20] and the incidence rate is increasing annually by 8%.[21] MCC typically presents in elderly patients (60–85 years old) or immunosuppressed patients, such as those with leukemia/lymphoma, advanced human immunodeficiency virus, or solid organ transplantation.[22] The majority of cases are seen in Caucasians, and the male to female ratio is approximately 5:4.[23],[24] MCC commonly involves sun-exposed areas of the body, especially the head and neck. An occasional association with squamous cell carcinoma has been noted.[25] Clinically, MCC presents as a pink-red to violaceous, firm, dome-shaped, solitary nodule with a shiny surface.[26] MCC grows rapidly and ulceration may occur.[27] Most MCC cases occur in the sun-exposed head and neck region, and those arising on sun-protected sites (such as in the oral cavity [28] or genital region [29]) have a particularly poor prognosis. The five most common clinical features are summarized in the acronym AEIOU: Asymptomatic/lack of tenderness, Expanding rapidly, Immunosuppression, Older than age 50, and Ultraviolet (UV) light-exposed site.[30]

Initial diagnosis of MCC is usually based on skin biopsy. Histologic sections reveal a dermal nodule that infiltrates the subcutaneous fat but spares the epidermis and adnexal structures.[25] Three histologic subtypes are recognized: (a) Intermediate cell type, with solid nests with trabeculae at the periphery, (b) small cell type, with sheets of small cells with a diffusely infiltrative pattern, and (c) trabecular type, with connective tissue separating interconnected cellular trabeculae. A lymphocytic infiltrate may surround or infiltrate the tumor cells. MCCs frequently contain areas that histologically resemble BCC, with mucinous stroma or artifactual stromal retraction. The most reliable histologic feature to distinguish BCC from MCC is the absence of peripheral palisading in MCC.[31],[32] Immunohistochemical staining for BerEP4 is positive in BCC, but negative in MCC.[25] Treatment for skin lesions usually involves surgical excision, but local recurrence rates may be as high as 40%. Of the patients with recurrences, 75% will develop nodal or distant metastases.[25]

FNA can be performed to assess metastatic disease in patients with a prior diagnosis of MCC. Common FNA sites include the cervical lymph nodes, parotid gland, or axillary and inguinal nodes, with rare reported cases in the chest, proximal extremities, pancreas,[33] and ascites.[34] The reported rate of liver metastases is up to 13%,[35] yet MCC cytology specimens from the liver are seldom described in literature.[36] The presence of a solitary MCC metastasis with limited clinical history, as seen in our case, can be diagnostically challenging if one is not actively considering it. Certain cytomorphologic features may assist in identification. MCC typically yields cellular smears with numerous small round cells in a dispersed or loosely cohesive pattern [Figure 2]. The relatively monomorphic nuclei have finely granular, dusty chromatin and may show the typical endocrine “salt and pepper” appearance. Nucleoli are not easily observed. Mitotic figures may be prominent. Apoptotic bodies are often present, but necrosis is infrequent. Crush artifact and nuclear molding are not typically identified, but rare aggregates of tumor cells may infrequently produce a pseudorosette appearance. Cytoplasm is scanty or absent, and rare eosinophilic paranuclear cytoplasmic globules or buttons have been described.[36],[37]
Figure 2: Fine needle aspiration of a solitary 5.5 cm hypermetabolic anterior mediastinum mass from a 69-year-old man with a previously resected right buttock Merkel cell carcinoma, (a) The high cellularity and loosely cohesive nature (Romanowsky, ×4); (b) The finely granular chromatin and round small nuclei (Papanicolaou, ×40); (c) Similar features (H and E of the cell block, ×40); (d) The malignant cells (Cytokeratin-20 of the cell block, ×40)

Click here to view

Immunohistochemistry is very important to distinguish MCC from its mimics. MCC shows a characteristic perinuclear dot-like CK-20 positivity.[38],[39] Small cell carcinoma [Figure 3] and other neuroendocrine tumors are typically CK-20 negative although they share neuroendocrine markers (such as chromogranin, synaptophysin, and CD56) with MCC.[13],[40] MCC is negative for CK-7, BerEp4, thyroid transcription factor 1, CD45, and mucicarmine; these stains distinguish it from mimics such as lymphoma [Figure 4] and cholangiocarcinoma [Figure 5]. CM2B4, a relatively new marker that targets MCPyV T-antigen, is expressed in most cases. CM2B4 is very helpful in distinguishing MCC from high-grade primary parotid neuroendocrine tumors (which regularly show CK-20 expression) and rare extrapulmonary small cell carcinomas with focal CK-20 expression.[12],[13]
Figure 3: Small cell carcinoma involving the liver, (a) with nuclear crowding and crush artifact (Romanowsky, ×10); (b) Nuclear molding (Papanicolaou, ×40); (c) Infiltration of liver parenchyma by small dark cells with crush artifact H and E (cell block, ×20); (d) The cells stained with thyroid transcription factor 1 (shown) as well as synaptophysin and CD56 (not shown)

Click here to view
Figure 4: Lymphoma. (a) Follicular lymphoma with a monotonous population of small lymphocytes, Romanowsky smear, ×40, with associated cell block, H and E, ×40 (b). (c) Diffuse large B-cell lymphoma with large atypical discohesive cells and distinct nucleoli, Romanowsky smear, ×40, with associated cell block, H and E, ×40 (d)

Click here to view
Figure 5: Cholangiocarcinoma. (a) Clusters of small dark cells (Romanowsky smear, ×40); (b) (Papanicolaou smear, ×20); (c) Cell block with glandular clusters of cuboidal cells (H and E, ×20); (d) Strong staining for cytokeratin-7 (×20)

Click here to view

In addition to surgery, chemotherapy and radiation therapy can improve overall survival. The combination of chemotherapy and radiation therapy provide more benefit than radiation therapy alone, especially in high-risk patients.[41],[42],[43] Our patient presented had severe COPD, making him oxygen dependent at home, and he opted to have radiation therapy alone secondary to his comorbidities.

In summary, MCC is a rare but aggressive malignancy with the potential for spread to the lymph nodes and distant metastasis. A solitary metastatic MCC lesion can be a challenging cytologic diagnosis, especially if limited history is available. In patients with an appropriate clinical profile (immunosuppression or elderly Caucasian men) and cytomorphology (a cellular specimen with loosely cohesive round cells with salt-and-pepper chromatin and frequent mitoses), MCC should be considered in the differential. Immunohistochemical staining for CK-20 and further inquiry into patient history can yield an appropriate diagnosis.

 » Competing Interests Statement by All Authors Top

The authors declare that they have no competing interests.

 » Authorship Statement by All Authors Top

All authors of this article declare that we qualify for authorship as defined by ICMJE http://www.icmje.org/#author. Each author has participated sufficiently in work and takes public responsibility for appropriate portions of the content of this article.

 » Ethics Statement by All Authors Top

As this is a quiz case without identifiers, our institution does not require approval from the Institutional Review Board (or its equivalent).

 » List of Abbreviations (In Alphabetic Order) Top

BCC - Basal cell carcinoma

CD - Cluster of differentiation

CT - Computed tomography

CK - Cytokeratin

FNA - Fine needle aspiration

MCC - Merkel cell carcinoma.

 » References Top

Shattuck TM, Waugh MS, Jones CK. Coincident Merkel cell carcinoma and B-cell lymphoma: A report of two cases evaluated by cytology. Diagn Cytopathol 2014;42:819-22.  Back to cited text no. 1
Santos-Juanes J, Fernández-Vega I, Fuentes N, Galache C, Coto-Segura P, Vivanco B, et al. Merkel cell carcinoma and Merkel cell polyomavirus: A systematic review and meta-analysis. Br J Dermatol 2015;173:42-9.  Back to cited text no. 2
Feng H, Shuda M, Chang Y, Moore PS. Clonal integration of a polyomavirus in human Merkel cell carcinoma. Science 2008;319:1096-100.  Back to cited text no. 3
Houben R, Angermeyer S, Haferkamp S, Aue A, Goebeler M, Schrama D, et al. Characterization of functional domains in the Merkel cell polyoma virus Large T antigen. Int J Cancer 2015;136:E290-300.  Back to cited text no. 4
Cimino PJ, Robirds DH, Tripp SR, Pfeifer JD, Abel HJ, Duncavage EJ. Retinoblastoma gene mutations detected by whole exome sequencing of Merkel cell carcinoma. Mod Pathol 2014;27:1073-87.  Back to cited text no. 5
Edge SB, Byrd DR, Compton CC, Fritz AG, Greene FL, Trotti A, et al., editors. Merkel cell carcinoma. AJCC Cancer Staging Manual. 7th ed. New York: Springer; 2010. p. 315-23.  Back to cited text no. 6
Allen PJ, Bowne WB, Jaques DP, Brennan MF, Busam K, Coit DG. Merkel cell carcinoma: Prognosis and treatment of patients from a single institution. J Clin Oncol 2005;23:2300-9.  Back to cited text no. 7
Andea AA, Coit DG, Amin B, Busam KJ. Merkel cell carcinoma: Histologic features and prognosis. Cancer 2008;113:2549-58.  Back to cited text no. 8
Skelton HG, Smith KJ, Hitchcock CL, McCarthy WF, Lupton GP, Graham JH. Merkel cell carcinoma: Analysis of clinical, histologic, and immunohistologic features of 132 cases with relation to survival. J Am Acad Dermatol 1997;37(5 Pt 1):734-9.  Back to cited text no. 9
Llombart B, Monteagudo C, López-Guerrero JA, Carda C, Jorda E, Sanmartín O, et al. Clinicopathological and immunohistochemical analysis of 20 cases of Merkel cell carcinoma in search of prognostic markers. Histopathology 2005;46:622-34.  Back to cited text no. 10
Mott RT, Smoller BR, Morgan MB. Merkel cell carcinoma: A clinicopathologic study with prognostic implications. J Cutan Pathol 2004;31:217-23.  Back to cited text no. 11
Busam KJ, Jungbluth AA, Rekthman N, Coit D, Pulitzer M, Bini J, et al. Merkel cell polyomavirus expression in merkel cell carcinomas and its absence in combined tumors and pulmonary neuroendocrine carcinomas. Am J Surg Pathol 2009;33:1378-85.  Back to cited text no. 12
Bechert CJ, Schnadig V, Nawgiri R. The Merkel cell carcinoma challenge: A review from the fine needle aspiration service. Cancer Cytopathol 2013;121:179-88.  Back to cited text no. 13
Maricich SM, Wellnitz SA, Nelson AM, Lesniak DR, Gerling GJ, Lumpkin EA, et al. Merkel cells are essential for light-touch responses. Science 2009;324:1580-2.  Back to cited text no. 14
Moll I, Roessler M, Brandner JM, Eispert AC, Houdek P, Moll R. Human Merkel cells – Aspects of cell biology, distribution and functions. Eur J Cell Biol 2005;84:259-71.  Back to cited text no. 15
Merkel F. Tastzellen and tastkoerperchen bei den hausthieren und beim menschen. Arch Mikrosk Anat 1875;11:636-52.  Back to cited text no. 16
Toker C. Trabecular carcinoma of the skin. Arch Dermatol 1972;105:107-10.  Back to cited text no. 17
De Wolff-Peeters C, Marien K, Mebis J, Desmet V. A cutaneous APUDoma or Merkel cell tumor? A morphologically recognizable tumor with a biological and histological malignant aspect in contrast with its clinical behavior. Cancer 1980;46:1810-6.  Back to cited text no. 18
Tilling T, Moll I. Which are the cells of origin in merkel cell carcinoma? J Skin Cancer 2012;2012:680410.  Back to cited text no. 19
Schrama D, Ugurel S, Becker JC. Merkel cell carcinoma: Recent insights and new treatment options. Curr Opin Oncol 2012;24:141-9.  Back to cited text no. 20
Hodgson NC. Merkel cell carcinoma: Changing incidence trends. J Surg Oncol 2005;89:1-4.  Back to cited text no. 21
Hasan S, Liu L, Triplet J, Li Z, Mansur D. The role of postoperative radiation and chemoradiation in merkel cell carcinoma: A systematic review of the literature. Front Oncol 2013;3:276.  Back to cited text no. 22
Smith PD, Patterson JW. Merkel cell carcinoma (neuroendocrine carcinoma of the skin). Am J Clin Pathol 2001;115 Suppl: S68-78.  Back to cited text no. 23
Albores-Saavedra J, Batich K, Chable-Montero F, Sagy N, Schwartz AM, Henson DE. Merkel cell carcinoma demographics, morphology, and survival based on 3870 cases: A population based study. J Cutan Pathol 2010;37:20-7.  Back to cited text no. 24
Mills SE, Darryl C. (2010). Sternberg's Diagnostic Surgical Pathology. 5th edPhiladelphia, PA: Lippincott Williams and Wilkins.  Back to cited text no. 25
Jaeger T, Ring J, Andres C. Histological, immunohistological, and clinical features of merkel cell carcinoma in correlation to merkel cell polyomavirus status. J Skin Cancer 2012;2012:983421.  Back to cited text no. 26
Ratner D, Nelson BR, Brown MD, Johnson TM. Merkel cell carcinoma. J Am Acad Dermatol 1993;29(2 Pt 1):143-56.  Back to cited text no. 27
Yom SS, Rosenthal DI, El-Naggar AK, Kies MS, Hessel AC. Merkel cell carcinoma of the tongue and head and neck oral mucosal sites. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:761-8.  Back to cited text no. 28
Coleman NM, Smith-Zagone MJ, Tanyi J, Anderson ML, Coleman RL, Dyson SW, et al. Primary neuroendocrine carcinoma of the vagina with Merkel cell carcinoma phenotype. Am J Surg Pathol 2006;30:405-10.  Back to cited text no. 29
Heath M, Jaimes N, Lemos B, Mostaghimi A, Wang LC, Peñas PF, et al. Clinical characteristics of Merkel cell carcinoma at diagnosis in 195 patients: The AEIOU features. J Am Acad Dermatol 2008;58:375-81.  Back to cited text no. 30
Shipkov CD, Dumollard JM, Mojallal A, Seguin P. Merkel cell carcinoma vs. basal cell carcinoma: Histopathologic challenges. J Cutan Pathol 2008;35:789-90.  Back to cited text no. 31
Ball NJ, Tanhuanco-Kho G. Merkel cell carcinoma frequently shows histologic features of basal cell carcinoma: A study of 30 cases. J Cutan Pathol 2007;34:612-9.  Back to cited text no. 32
Bernstein J, Adeniran AJ, Cai G, Theoharis CG, Ustun B, Beckman D, et al. Endoscopic ultrasound-guided fine-needle aspiration diagnosis of Merkel cell carcinoma metastatic to the pancreas. Diagn Cytopathol 2014;42:247-52.  Back to cited text no. 33
Policarpio-Nicolas ML, Avery DL, Hartley T. Merkel cell carcinoma presenting as malignant ascites: A case report and review of literature. Cytojournal 2015;12:19.  Back to cited text no. 34
Voog E, Biron P, Martin JP, Blay JY. Chemotherapy for patients with locally advanced or metastatic Merkel cell carcinoma. Cancer 1999;85:2589-95.  Back to cited text no. 35
Skagias L, Evangelou I, Kyriakidou V, Ntinis A, Politi E. Diagnostic approach to a solitary liver mass composed of small round blue cells. Cytopathology 2009;20:56-8.  Back to cited text no. 36
Shield PW, Crous H. Fine-needle aspiration cytology of Merkel cell carcinoma – A review of 69 cases. Diagn Cytopathol 2014;42:924-8.  Back to cited text no. 37
Scott MP, Helm KF. Cytokeratin 20: A marker for diagnosing Merkel cell carcinoma. Am J Dermatopathol 1999;21:16-20.  Back to cited text no. 38
Domagala W, Lubinski J, Lasota J, Giryn I, Weber K, Osborn M. Neuroendocrine (Merkel-cell) carcinoma of the skin. Cytology, intermediate filament typing and ultrastructure of tumor cells in fine needle aspirates. Acta Cytol 1987;31:267-75.  Back to cited text no. 39
Pisharodi LR, Bedrossian C. Diagnosis and differential diagnosis of small-cell lesions of the liver. Diagn Cytopathol 1998;19:29-32.  Back to cited text no. 40
Eng TY, Boersma MG, Fuller CD, Goytia V, Jones WE 3rd, Joyner M, et al. A comprehensive review of the treatment of Merkel cell carcinoma. Am J Clin Oncol 2007;30:624-36.  Back to cited text no. 41
Bichakjian CK, Lowe L, Lao CD, Sandler HM, Bradford CR, Johnson TM, et al. Merkel cell carcinoma: Critical review with guidelines for multidisciplinary management. Cancer 2007;110:1-12.  Back to cited text no. 42
Chen MM, Roman SA, Sosa JA, Judson BL. The role of adjuvant therapy in the management of head and neck merkel cell carcinoma: An analysis of 4815 patients. JAMA Otolaryngol Head Neck Surg 2015;141:137-41.  Back to cited text no. 43


  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]


Previous article Next article


  Site Map | Copyright and Disclaimer
© 2007 - CytoJournal | A journal by Cytopathology Foundation Inc with Wolters Kluwer - Medknow
New version online since 1st July '08
Open Access